package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.Voucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import org.springframework.aop.framework.AopContext;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;
import java.time.LocalDateTime;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public  class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    @Resource
    private RedisIdWorker redisIdWorker;

    @Resource
    private ISeckillVoucherService seckillVoucherService;

    @Resource
    private StringRedisTemplate stringRedisTemplate;



    @Override
    public Result seckillVoucher(Long voucherId) {
        //1.查询优惠劵
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
        //2.判断是否可以秒杀，秒杀是否开始或者结束
        if (voucher.getBeginTime().isAfter(LocalDateTime.now()) || voucher.getEndTime().isBefore(LocalDateTime.now())) {
            return Result.fail("秒杀还未开始或者已经结束!");
        }
        Long userId = UserHolder.getUser().getId();
        //TODO 查询订单
        int count = query().eq("user_id", userId).eq("voucher_id", voucherId).count();
        //TODO
        if (count > 0) {
            //用户已经购买过了
            return Result.fail("用户已经购买过一次！");
        }
        //3判断库存是否充足
        if (voucher.getStock() < 1) {
            return Result.fail("库存不足!");
        }
        //4.减库存
        boolean success = seckillVoucherService.update()
                .setSql("stock = stock - 1")
                .eq("voucher_id", voucherId).gt("stock", 0).update();
        if (!success) {
            return Result.fail("库存不足!");
        }
        //创建锁对象
        SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, stringRedisTemplate);
        //获取锁
        boolean isLock = lock.tryLock(1200);
        if (!isLock) {
            //获取锁失败
            return Result.fail("一个人只允许下一单!");
        }
        try {
            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
            return proxy.createVoucherOrder(voucherId);
        } catch (IllegalStateException e) {
            throw new RuntimeException(e);
        } finally {
            lock.unlock();
            //释放锁
        }


    }

    @Override
    public Result createVoucherOrder(Long voucherId) {
        //TODO 一人一单
        Long userId = UserHolder.getUser().getId();
        //5.创建订单
        VoucherOrder voucherOrder = new VoucherOrder();
        //5.1 订单id-
        long orderId = redisIdWorker.nextId("order");
        voucherOrder.setId(orderId);
        //5.2 用户id
        voucherOrder.setUserId(userId);
        //5.3 优惠劵id
        voucherOrder.setVoucherId(voucherId);
        //将订单信息写入数据库
        save(voucherOrder);
        //6.返回订单信息
        return Result.ok(orderId);
    }

}
